Surgical Hand Scrubs: Why Your Veterinarian Washes Their Hands So Carefully Before Surgery

By Steve Mehler, DVM, DACVS

When your dog or cat goes into surgery, you probably expect your veterinarian to wash their hands first.

But have you ever wondered why the process is so long, so specific, and so different from the way we normally wash our hands?

The answer comes down to one simple goal:

Protecting your pet from a surgical site infection.

A surgical hand scrub is one of the oldest—and still one of the most important—infection prevention practices in both human and veterinary medicine.

Why Are Surgical Hand Scrubs Different?

A quick hand wash removes dirt and many of the germs we pick up throughout the day.

A surgical hand scrub goes much further.

Its purpose is to:

• Remove dirt and debris

• Reduce the number of bacteria living on the skin

• Suppress bacterial growth during the entire surgical procedure

• Lower the chance that bacteria contaminate sterile gloves if a microscopic glove puncture occurs

Even perfectly healthy skin naturally contains millions of bacteria. While most of these bacteria are harmless on the outside of the body, they can cause serious infections if introduced into a surgical incision.

Two Types of Bacteria Live on Our Hands

Transient bacteria

These are bacteria we pick up from touching patients, equipment, keyboards, phones, or door handles.

They're relatively easy to remove with proper hand washing.

Resident bacteria

These bacteria live deeper within the skin, hair follicles, and sweat glands.

They are much harder to eliminate completely.

The goal of a surgical hand scrub isn't to sterilize the hands—that's impossible.

Instead, it's to reduce bacterial numbers to the lowest level possible and keep them suppressed during surgery.

The Traditional Surgical Scrub

For decades, veterinary surgeons performed timed scrubs lasting 5 to 10 minutes using antimicrobial soap and sterile brushes.

The process typically included:

• Fingernails

• Fingertips

• Fingers

• Hands

• Forearms to the elbows

This ritual became a symbol of surgery itself.

But research has taught us that longer isn't always better.

Scrubbing Too Hard Can Actually Be a Problem

One surprising finding from modern research is that aggressive scrubbing with stiff brushes can damage the skin.

Damaged skin develops tiny cracks that actually harbor more bacteria.

Today, many surgeons use:

• Soft disposable sponges

• Nail picks only when necessary

• Gentle friction instead of aggressive scrubbing

Protecting the skin barrier is now considered an important part of infection prevention.

What Solutions Are Used?

The two most common surgical hand antiseptics are:

Chlorhexidine Gluconate (CHG)

Advantages:

• Excellent activity against many bacteria

• Continues working for hours after application

• Excellent residual activity

Potential disadvantages:

• Can irritate sensitive skin

• Less effective against certain spores

Povidone-Iodine

Advantages:

• Broad antimicrobial activity

• Effective against bacteria, viruses, fungi, and many other organisms

Potential disadvantages:

• Less residual activity than chlorhexidine

• Activity can decrease if large amounts of organic material remain on the skin

Alcohol-Based Surgical Hand Rubs

Many hospitals—including veterinary specialty hospitals—now use alcohol-based hand rubs after an initial hand wash.

These products often combine:

• 60–90% alcohol

• Chlorhexidine

• Moisturizers

Research has shown they:

• Kill bacteria rapidly

• Cause less skin damage

• Are faster to use

• Often achieve bacterial reductions equal to or better than traditional scrubs

Many surgical guidelines now recommend alcohol-based surgical hand preparation as the preferred technique when hands are not visibly soiled.

What About Fingernails?

Your veterinarian's nails are probably shorter than average—and that's intentional.

Long nails:

• Harbor more bacteria

• Increase glove puncture risk

• Make cleaning underneath the nails more difficult

Artificial nails and chipped nail polish have also been associated with increased bacterial contamination in healthcare settings.

Jewelry Has to Go

Before scrubbing, surgeons remove:

• Rings

• Watches

• Bracelets

These items trap bacteria and prevent proper cleaning.

Even a wedding ring creates tiny spaces where microorganisms can hide.

Does the Water Temperature Matter?

Surprisingly, yes.

Very hot water can damage the skin and increase irritation.

Current recommendations generally favor lukewarm water because it is gentler on the skin while still allowing effective cleaning.

The Scrub Is Only the Beginning

After the surgical hand preparation comes another critical step:

Sterile gowning and gloving.

Even perfectly scrubbed hands are never considered sterile.

Instead, the hand scrub dramatically reduces bacterial contamination before sterile gloves are applied.

If gloves develop an unnoticed tear during surgery, the lower bacterial count on the surgeon's hands reduces the risk of contamination.

Modern Infection Prevention Is Layered

A successful surgery doesn't rely on just one step.

Veterinary teams combine multiple protective measures, including:

• Surgical hand antisepsis

• Sterile gowns and gloves

• Proper patient skin preparation

• Sterile instruments

• Appropriate antibiotic use when indicated

• Careful surgical technique

• Temperature control

• Gentle tissue handling

• Meticulous closure

Each step reduces infection risk a little more.

Together, they create an extremely safe surgical environment.

The Bottom Line

The surgical hand scrub may seem simple, but it's one of the most important rituals in the operating room.

Modern research has shown that it's not about scrubbing harder or longer—it's about using evidence-based techniques that reduce bacteria while protecting the skin.

Every careful step your veterinary surgical team takes before making the first incision is designed with one goal in mind:

Giving your pet the safest surgery possible and the best chance for an uncomplicated recovery.